[แก้ไขแล้ว] Refund taxes

Antecedentes del problema:
We are a company based in the Canary Islands, Spain. We are exempt from VAT according to EU regulations. I am trying to remove the VAT from the invoice.

Síntomas:
VAT is not being removed from the invoice as expected.

Preguntas:
How can I remove the VAT from the invoice?